碩士 / 國立臺灣海洋大學 / 環境生物與漁業科學學系 / 104 / Swordtip squid (Uroteuthis edulis) is one of the main target species of torch-light fishery in the shelf waters of northeastern Taiwan. Swordtip squid is a migratory specie and distribute in the depth 30 to 170m of tropical and subtropical areas. In this study, we collected the logbooks of the Taiwanese stick-helddip fleets and marine environmental data, including sea surface temperature, chlorophyll-a, sea surface height anomaly of the northeastern waters of Taiwan during the period of 2009 to 2013. Acoording to fish data, we distinguish to spring group (Dec.~May.) and autumn groups (Jun.~Nov.). The generalized additive models (GAMs) were used to investigate the relationships between environmental variables and catch rates for evaluating the fishing condition of swordtip squid in the northeastern waters of Taiwan.
The results showed the major fishing season of swordtip squid were in the spring and autumn (52% and 59%, respectively) and the gravity of fish ground also showed the season variations in the period of 2009 and 2013. The model selection processes showed the cumulative deviances explained by the selected GAMs were 53.8% and 59.3% in the spring and autumn group, respectively. All of factors are significant correlation besides Chl-a in the spring group and Chl-a GM in the autumn group. The predicted catch rates showed the highly correlation with observed catch rates and had year and seasonal variations. In winter predicated highly catch rates mainly concentrated in the coastal of China and continental shelf along the coast of East China Sea, and gradually extending to the northeast off the coast of Taiwan during the spring. The highly catch rates would appeared in the northeast waters of Taiwan and northern Taiwan Strait in the autumn. Finally, the predicated catch rates on 2013 based on the GAM mode of 2009~2012 also showed same variation of fishing grounds with observed catch rates.
| Identifer | oai:union.ndltd.org:TW/104NTOU5451029 |
| Date | January 2016 |
| Creators | Ho, Hsin-Ying, 何欣穎 |
| Contributors | Lan, Kuo-Wei, Liao, Cheng-Hsin, 藍國瑋, 廖正信 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 83 |
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